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Table 1. Kinetic parameters derived from the least squares computer analysis applied to the hybridization
values obtained with hnRNA from normal and leukemic cells
CelIType First component Second component Third component
% K Cot 1 / 2 %
Normal
promyelocytes 7.3 3.66125 0.273 9.4
Normal
promyelocytes 5.7 1.97528 0.534 11.2
Normal
lymphoblasts 5.1 0.60000 1.666 9.7
Normal
lymphoblasts 4.4 0.76000 1.403 14.0
ALL 4.6 3.55457 0.280 29.0
AML1 10.7 0.59314 1.68 30.7
AML2 10.6 0.52518 1.90 38.9
HL60 5.9 0.43278 2.30 25.2
HL60 5.3 2.09849 0.47 24.6
K Cot1/2 % K Cot1/2
0.00992 100 26.8 0.00004 24870
0.00759 120 29.5 0.00004 25125
0.00473 211 28.8 0.00004 23192
0.00863 180 29.6 0.00006 17808
0.00317 315
0.00211 474
0.00206 484
0.00180 554
0.00261 382
hnRNA from different cell types ranging from
40% to 60%. Whereas some of them (Kline et
al. 1974) assurne that the hnRNA which fails
to hybridize belongs exclusively to the low
frequency dass of sequences, other authors
(Spradling et al. 1974) believe that the incomplete
hybridization of RNA in vast DNA
excess may affect all classes of sequences
equally. Whatever interpretation finally proves
to be correct, our results indicate that at
least part of the hnRNA of leukemic cells is
characterized by a sequence frequency higher
than that of hnRNA of normal cells.
Acknowledgments
This research was supported by a grant from the
National Research Council PFCCN contract no.
79.0068.396.
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